Consistent with NIH priorities, our long-term objective is to reduce the rates and risk of childhood obesity via school-based nutrition and physical activity policies. We propose to monitor and evaluate how Connecticut's first-ranked School Wellness Policy, in the New Haven Public School district, is implemented and determine its impact on children's obesogenic behaviors, weight outcomes, and school performance. We will evaluate a strategy of implementation at 12 targeted schools using a randomized design. We propose a multi-level assessment of factors that may influence childhood obesity using the Ecological Model as a guiding framework. This ambitious project is possible because of the expertise and strong collaborative partnerships between The New Haven Public Schools and two Yale University research centers: The Rudd Center for Food Policy and Obesity and CARE: Community Alliance for Research and Engagement. This study is designed to significantly advance empirical research on school wellness policies through targeted implementation and measurable impact on student health. Specific Aims are to: (1) track and evaluate a strategy of targeted school implementation of a District Wellness Policy; (2) identify factors that facilitate or impede implementation of The District Wellness Policy; and (3) evaluate the impact of implementation of The School Wellness Policy on obesogenic behaviors and health outcomes as well as school performance. We will implement nutrition and physical activity policies in 12 schools using a randomized 2 x 2 research design. This will permit comparison of unique and synergistic effects of nutrition and physical activity policies on student behaviors and health outcomes. We will follow a cohort of 5th grade students (NH700) annually for 4 years to assess potential changes in student eating behaviors, physical activity levels, and BMI. We use a multi-method approach to collect data and examine predictors of these outcomes from across the ecological framework: student variables, family characteristics, school policies, and neighborhood features (e.g., via environmental mapping and US Census Bureau statistics). This multidisciplinary proposal is synchronous with research objectives articulated in Program Announcement (PA-10-052) School Nutrition and Physical Activity Policies, Obesogenic Behaviors and Weight Outcomes. We directly target implementation and impact of health-related policies in schools; we have an active tracking system to monitor policies; and we focus on minority populations traditionally vulnerable and underserved. As stated by NIH, policy-based approaches to combat obesity in schools exist; however, knowledge is lacking in key areas concerning the optimal policies, key implementation strategies for such policies, and the impact of these policies on important health and social outcomes. The proposed project will advance scientific knowledge and understanding provide important evidence to guide future interventions in schools and communities - translating science to improved health of the public.